Fuse plug



Apr. 24, 1923. 1,453,170

HVT. PAISTE FUSE PLUG Filed Dec. 21, 1917 PatentedApr. at, was.

P i :H :.-d r J titan HENRY E. PAISTE, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR 1'0 TEE. IE. PAISTE CtlMPANY, 6F PHILADELPHIA, PENNSYLVANIA, A GGRPQBATZUN Oi PENNQYL- VANIA.

FUSE PLUG.

Application filed December 21, 1917. Serial lilo. 2085302.

To all whom it may concern:

Be it known that l, HENRY T. PArsrn, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented.

a Fuse lug, of which the following is a specification.

This invention relates to fuse plugs designed to be screwed into a suitable socket or receptacle and including a fuse-carrying no element or capsule independent of and removable from the body of the plug, one object of said invention being to so construct the body and capsule that their relative to tation under operating conditions shall be 5 prevented.

A further object of the invention is to provide a fuse plug of the above noted type in which the operation of screwing the plug into its socket or receptacle shall press together certain of the contacts of the device, the invention also contemplating novel means for insuring good electrical contact between one end of the fuse strip or other fusible member on the capsule and a portion of the threaded shell on the body.

It is also desired to provide a fuse plug having an opening through its body, with novel means for mounting and holding in place the mica sheet or plate closing one end 0 of said opening, the invention also contemplating novel means for frictionally holding together the parts of a two part fuse plug.

These objects and other advantageous ends I secure as hereinafter set forth, reference being had to the accompanying drawin s, in which,

igs. 1 and 2, are respectively a side elevation and a plan of a fuse plug constructed according to my invention,

Figs. 3 and 4 arevertical longitudinal sections of the body and capsule respectively,

l1*"ig. 5, is a perspective view of the capsu e,

' Fig. 6, is a perspective view of the friction tongue-carrying ring, and

Fig. 7, is a perspective view of the fuse strip.

In the above drawings, 1 represents the body of my fuse plug which is preferably made of vitreous material such as porcelain and includes a substantially cylindrical body portion 2 having an outwardly extending peripherally notched flange 3. Extending through the body there is an opening or cavity which for the most part is of a cross section other than circular, in the present case hexagonal, and at one end of this opening is an inwardly extending flange l. The passage through said flange is normally closed by a circular or other suitably formed sheet 5 of mica or other transparent material held in place against the flange by a spring ring 6 of such construction that it tends to expand and therefore frictionally grips the walls of the main or hexagonal portion 7 of the cavity in the body. An Edison threaded terminal shell 8 is mounted on the cylindrical portion 2 of the body where it is normally held by its inwardly turned end 9 which is spun into an angular groove 10 of the body, the opposite end of said shell being formed with a fiat inwardly extending flange 11 normally resting against or immediately adjacent the end of the body. This shell is ordinarily free to turn on the body 1 and the opening through its flange 11 has the same form and dimensions as the passage or cavity 7 through the body.

The capsule 12 of the fuse plug consists of an elongated portion 13 of a cross section other than circular, in the present instance being made in the form of a hollow hexagonal prism. At one end of'the capsule there is formed an outwardly extending flange 14 which also extends inwardly so as to close one rind of the opening 15 through the main portion of the capsule. A terminal disc 16 is mounted at the center of the closed end of the capsule and has a forked stem 17 projecting into the hollow 15 where it is soldered to one end of a fuse strip 18, which extends from said stem outwardly to the end of the opening 15, thence radially across said end, back toward the flange 14: and radially ontward on the flat under face of said flange.

Two opposite fiat "faces of the prismatic portion 13 are longitudinally grooved as indicated at 19 for the reception of the fuse strip 18 which extends through either one of them as may be most convenient, and for insuring. the uninterrupted fiow of current from the fuse strip to the shell 8 of the body when the two parts of the fuse plug are assembled, I provide a relatively thin sheet metal ring 20 having an external diameter slightly less than that of the flange 14 and formed with a hexagonal opening of such diameter as to fit the prismatic portion 13 of the capsule 12. At opposite points the inner edges of this opening are provided with two all) curved spring tongues 21 and 22, of which the first is so formed that it preferably extends on both sides of a straight line drawn from the edge to which. said tongue is connected and at right angles to the plane of the ring 20. As a result, when the ring 20 is placed on the capsule 12, as shown in Fig. 4 it rests upon and electrically engages the outwardly projecting part 23 of the fuse strip 18. Both of said tongues, under these conditions, extend into the two opposite grooves or channels 19 and in addition the tongue 21. projects outwardly beyond the fiat adjacent face of the part 13.

When the capsule is placed in the opening 7 of the body, its part 13 moreor less closely fits the latter and in addition the tongue 21 frictionally engages the adjacent wall of the body so as to more or less tightly hold the capsule in a given position. If now the plug be screwed into a socket or receptacle, the center terminal plate 16 of the capsule engages the center terminal of sand socket, and the flange 14 is forcibly pressed. toward the adjacent end of the body, thereby clamping the ring 20 between the inturned flange ll of theterminal shell 8 and the radially projecting end 23 of the fuse strip. circuit is thus completed from the terminal 16 through the fuse strip 18 and the ring 29 to the threaded shell 8.

It will be noted that while the shell 8 is free to rotate on the body 1 of the fuse plug as long as the capsule is not inserted, this latter element locks it to said body and prevents it from rotating when the parts are assembled, since the inner edge of the 'flange 11 engages the prismatic part 13 of the capsule which closely and non-rotatably fits the hexagonal or other non-circular opening in the ring 20 as well as the passage or cavity 7 of the body. 7

The condition of the fuse strip may be at all times observed through the mica or other transparent plate 5 and when said strip blows or fuses, the capsule may be quickly removed and replaced by another having its fuse strip intact. By making the threaded shell or sleeve 8 rotatable, the likelihood. of securing good electrical contact between the fuse strip and said shell is materially increased.

I claim 1. The combination in a fuse plug of a body having a cavity of polygonal cross section; a fuse-carrying capsule having a portion of prismatic form, removably and non-rotatably fitting said cavity and including a fusible strip projecting beyond a portion of its surface; with a contact on the end of the body adjacent the opening of said cavity electrically engaged by the projecting part of said strip.

2. The combination in a fuse plug of a body having a cavity for a removable fuse carrying element and including an extended portion. pro ecting into said cavity; a transparent closure for the cavity abutting said extended portion and prevented from outward. movement thereby; and means within the cavity for retaining said closure in place.

3. The combination in a fuse plug of a. tubular body inwardly flanged at one end and having a cavity for the reception of a removable fuse-carrying element; atransparent plat-e abutting the flange of said body within. the cavity tl1ereof;anda spring ring within the cavity for said element, operative to retain the plate in. position.

a. The combination in a fuse plug of a. hollow body; a capsule removably fitting the cavity of said body; with a member structurally independent of and operative-between the body and the capsule and encircling the latter for frictionally holding them together.

5. The combination in a fuse plug of a hollow body; a capsule removably fitting the hollow of said body; and an annular member structurally independent of the body and capsule having means for frictionally holding them together.

6. The combination in a fuse plug of a hollow body; a capsule removably fitting the cavity of said body; and a spring mngue structurally independent of and, operative between said parts for frictionally holding them together; with means for removablv holding the tongue on thecapsule. v

*4". The combination in a fuw plug of a hollow body; a capsule removably fitting the cavity or" said body; and a ring encircling the capsule, having at least one spring tongue extended between the body and the capsule for frictionally holding them together 8. The combination in a fuse plug of a body; a fuse capsule fitting the cavity thereof and hating a hangs; and a ring on said flange having at least one spring tongue extending between the capsule and the body for frictionally holding them together.

9. The combination in a fuse plug of a body; metal terminal shell on the body, having a portion extended over one end thereof; a flanged fuse capsule removably fitting the cavity of the body and including a fuse having a portion extended over the flange; with a metal rin on the capsule in. position to simultaneous y engage a part of the. fuse thereon and. also the inwardly turned portion of the terminal shell.

16. The combination in a fuse plug of a body having a cavity of other than circular cross section; a metal terminal shell rotatably mounted on the body and. inwardly flanged. over one end thereof; a fuse capsule having a portion of other than circular secgroove; with a ring mounted on the capsule and havin a tongue projecting into said groove an also extended into position to frictionally engage the wall of the cavity of the body.

11. The combination in a fuse plug of a hollow body having a metallic terminal shell inwardly flanged over one of its ends; an outwardly flanged fuse capsule fitting the cavity of said body and provided with at least one longitudinally extended groove; a fuse on the capsule including a portion extending outwardly over the flange thereof; and a metal ring mounted on the capsule between the flange and the inwardly extending portion of the terminal shell of the body.

12. The combination in a fuse plug-of a hollow body having a metallic terminal shell inwardly flanged over one of its ends; an outwardly flanged fuse capsule fitting the cavity of said body and provided with at least one longitudinally extended groove; a fuse for the capsule including a portion extending outwardly over the flange thereof; a metal ring mounted on the capsule between the flange and the inwardly extending portion of the terminal shell on the body; with at least one tongue on said ring in position to enter the groove and frictionally engage the wall of t e cavity.

13. The combination in a fuse plug of a body having a cavity of other than circular section; a metallic terminal shell rotatably mounted on the body and having an in-' wardly extending flange formed with an opening of substantially the same outline as that of said cavity; an outwardly flanged fuse capsule fitting the cavity of the body and including a fuse strip extended over said flange; and a metal ring slidably but non-rotatably mounted on the capsule and provided with a spring tongue frictionally en aging the wall of the cavity of the body.

n witness whereof I affix my signature.

HENRY T. PAISTE. 

